This section provides background information related to the present disclosure which is not necessarily prior art.
The manufacture of axle, shaft and other power/torque transmission components of the type used in vehicles, machines, commercial and industrial equipment and other devices often requires the formation of power/torque transmission features upon the external surfaces of round metal workpieces, in the form of rods, tubes, cylinders and other shapes. One exemplary manufacturing method involves spline rolling, which typically utilizes a pair of opposed, elongated, substantially parallel, reciprocating dies, tools or tool members (called “racks”) having a series of feature-forming surfaces, such as teeth, disposed in precision arrangements on facing surfaces thereof corresponding to, but not necessarily matching, the desired final surface features of the workpiece to be prepared. Accordingly, spline rolling typically involves reciprocating movement of the opposed dies, tools or tool members (called “racks”) over the length of a rotating workpiece, in opposite directions and in overlapping relationship, causing the feature-forming surfaces to displace material upon the surface of the rotating workpiece by applied pressure, in a cold-forming technique. The spline rolling operation thus forms the desired finished external surface features in the workpiece, typically helical or spur ridges, teeth or grooves (or “splines”), through the combination of the rotation of the workpiece with the linear reciprocating movement of the racks. Spline rolling racks are typically constructed in single or double-piece form, with either the single piece or both pieces of a double-piece rack being perishable. They are typically fastened upon suitable opposed, elongated, substantially parallel, reciprocating slide assemblies located within dedicated spline rolling machines of industrial grade.
The nature of forming the desired power/torque transmission features, such as splines, requires critical tolerances in the size and configuration of the feature-forming surfaces, and well as in the spacing, configuration and movement of the racks so that the desired surface features are accurately formed in the workpiece. Thus, these tooling components require precision-crafted feature-forming surfaces and precision mounting apparatus, supports and fasteners within the larger machines in which they are typically contained. However, these tooling components have a limited lifespan, with their feature-forming surfaces typically becoming worn or no longer within required tolerances after some period of their use.
Accordingly, at periodic intervals it is typically necessary to remove the surface-forming tooling components for replacement or resurfacing. Such components can typically be resurfaced a number of times before they can no longer be resurfaced, and as such, must then be replaced. Oftentimes, the manufacture and resurfacing of such tooling components is inefficient due to the time required to ship the components back to the manufacturer for resurfacing and back again to the user. Also, oftentimes, removal and replacement of such tooling components is time-consuming, burdensome and otherwise inefficient, due to the configuration and large size of the components, the current way in which the tooling components are secured in a work position, and the positioning and aligning activities that must typically take place for securing the components in a work position. Having such a machine in an idle state during required maintenance activities slows down overall production rates for any such affected facility, so it is advantageous for such maintenance to be made convenient, efficient and quick.
As examples, the tooling components requiring repair or replacement may be secured within the interior of a larger machine in a way that is inconvenient to manage, such as being secured with fasteners, such as bolts and set screws, that are difficult to reach and manipulate. In addition, the end of a spline rolling rack is typically the primary locating surface for gauging the proper mounting location of the rack within the machine, which can be inconvenient to measure or check for proper alignment. Also, the tooling components may not themselves be manufactured in sufficient tolerances for precision work, or the devices or features provided for facilitating proper positioning may not be sufficient or efficient to use. Proper alignment of the tooling components relative to each other must typically be ensured, which may only be provided in limited scope by relative adjustment of certain surfaces on the machine components when located within the machine that can be difficult to reach and/or examine. The final tolerances required in the feature-forming surfaces may also not be sufficient, or may be manufactured inefficiently, such as by preparing the feature-forming surfaces to required precision tolerances as the final step of the manufacturing process.
In addition, there is typically a substantial cost associated with the replacement or repair of the tooling components involved in such surface forming operations. The sizes of the components can be substantial, depending upon the sizes of the power/torque transmission components being manufactured, perhaps requiring substantial powered lifting equipment for assisting in this activity. The repair or replacement of the tooling components may require shipment and/or courier delivery of substantially-sized and weighted components, at considerable expense. Users of such tooling components must also manage a float of such tools at various levels of life and, due to the lead time required to manufacture new racks, must anticipate tools ending their life span and order new tools to arrive in conjunction with the retirement of existing tools.
In consideration of the above, the adoption of an improved configuration of such surface-forming tooling components along with an improved configuration of the associated devices used for retaining such components in required locations while maintaining the required tolerances for same, would provide significant maintenance efficiencies and cost benefits.